Brake for railroad vehicles



- Aug. 2,. 1932. ROHM 1,870,204

BRAKE FOR RAILROAD VEHICLES Filed July 19, 1930 mp/ wq.

Patented Aug. 2, 1932 UNITED s'raras JOSEIE ROHM, F WIENER-NEUSTA'DT, A'USTRIA BRAKE FOR RAILROAD VEHICLES Application filed July 19, 1930, Serial No. 469,189, and in Germany June 11, 1930.

The invention relates to brakes for vehicles which run on rails, of the type wherein a wedge-shaped brake member is interposed between the rail and the vehicle wheel.

The object of the invention is to improve the action of the brake by providing upon the wedge-shaped brake member a receptacle containing sand and causing the sand to issue from the receptacle in front of the brake member so that the latter will slide upon a rail surface covered with sand whereby the friction is considerably increased. The opening of the sand receptacle takes place by means of a member which preferably comes i into contact with the rail before the brake shoe reaches the rail.

The accompanying drawing shows by way of example one form of the invention.

f indicates a brake shoe the under surface of which is preferably made concave to fit the curved surface of the top of the rail 6. The rear surface of the brake shoe has preferably a curvature corresponding to that of the vehicle wheel 9. The drawing shows only one brake shoe and one wheel, but it will be understood that two identical brake shoes are used, one for each rail, the shoes being rigidly connected by a cross rod is. The two shoes are suspended from the undercarriage by spring members it pivotally fixed to the undercarriage at i, and they are normally held above the rails by being suspended from rods or cords 6 preferably from the drivers stand.

The brake shoe or its front portion forms a sand receptacle (Z, which has a closure flap Z carrying a roller a. The flap and the roller are pivotally mounted upon the sand receptacle at 0 in such a manner that when the brake shoe is lowered, the roller a will strike the rail 6 even before the brake shoe comes into contact with the rail 6 and will cause the flap Zto open, thus allowing the sand to issue from the receptacle in front of the brake shoe.

The brake shoe is rounded at the front end of its lower surface to avoid any accidental jamming of the brake shoe in a joint between two rails, and also in order to avoid any damage to the rail. At the rear end of the brake shoe there are provided cast on projections which are curved outwardly to facilitate elillgagement between the wheel and the brake s cc.

The operation of the brake is as follows If it is desired to brake the vehicle very rapidly within a very short stretch, the brake shoes are released from the drivers stand and they descend by their own gravity upon the rails, the rollers a striking first the rails. Upon the rollers a coming into contact with the rails the flaps Z pivoted at 0 open and cause the sand to issue from the receptacle so that the brake shoes come into contact with sand covered rail surfaces. During the forward movement of the wheels 9 the brake shoes are forced between the wheels and the rails and effect very rapid braking of the vehicle within a very short distance.

I claim 1. A brake for railroad vehicles, comprising in combination: a brake shoe normally suspended above the rail; means for bringing said brake shoe into contact with the rail; a sand receptacle provided in said brake shoe; a pivoted closure flap for controlling the issue of the sand from the receptacle; a roller upon said pivoted closure flap, said roller being so arranged as to come int-o contact with the rail before the brake shoe reaches the rail.

2. A brake for railroad Vehicles comprising in combination: a vehicle frame portion; a wedgeshaped brake shoe; a suspension spring for connecting said brake shoe to said frame portion; a releasable means for holding the brake shoe above the rail; a sand receptacle upon said brake shoe, a pivoted closure flap; and a roller upon said pivoted closure flap adapted to come into contact with the rail before the brake shoe reaches the rail,

3. A brake for railroad vehicles comprising in combination: a vehicle frame; a wedgeshaped brake shoe suspended from said vehicle frame 5 means for releasing said brake shoe; a wedge-shaped sand receptacle arranged above that end of said brake shoe which is located in front with regard to the direction of travel of the vehicle; aclosure flap arranged at the bottom of said wedgem shaped sand receptacle; and means for opening said flap operable by contact with the rail whereby sand is caused to issue from said receptacle and cover the rails in front of said brake shoe, substantially as described. Signed at Vienna, Austria, this 1st day of July, 1930.

ING. JOSEF ROHM. 

